It has been shown in previous studies that electrolytic lesions in the estrogen-sensitive nucleus intercollicularis (ICo) disrupt female nest-coos and male courtship induced ovarian development in the ring dove. In this proposal we analyze the underlying neural circuitry and neuroendocrine mechanisms with the methods for electrolytic lesion, selective chemical lesion, electrophysiological recordings and immunohistochemistry. Three interrelated studies are proposed: (1) Study of the role of the ICo neurons, (2) Role of telencephalic centers, such as nucleus taenia, an estrogen sensitive region which sends projections to the ICo, and (3) Role of the ICo projections to pre-optic-anterior hypothalamic region, an area concentrated with gonadotrophin releasing hormone neurons, with respect to the production of nest-coo display (vocal and posture component) and ovarian response to different coos. The long-term goal of these studies is to delineate the neural and endocrine mechanisms underlying the behaviorally mediated ovarian activity. These lines of studies may eventually help to understand and control of well-known clinical phenomenon such as the promotion of a woman's chance to conceive a child by adopting one.